1. Scope of Invention
This invention relates generally to spinning tops, and more particularly to a spinning top having a precision bearing which provides free relative rotation for a replaceable lower tip of the spinning top for enhanced performance.
2. Prior Art
The spinning top has been long known as an enjoyable toy for both children and adults. Such a spinning top includes a concentrically balanced body, typically tapered to a lower point or tip. The top, when spun rapidly as released, will continue to spin atop a support surface on the lower tip for an extended time period depending upon initial speed, inertia and friction. These conventional spinning tops are used in conjunction with a length of string which is wrapped tightly around the lower portion of the top and then thrown with the proximal end of the string being held between the fingers. The spinning top is released from the string in a rapidly spinning motion and, by gyroscopic effect, maintains the released orientation of the spin axis, which spinning motion continues as the top comes to rest on a support surface at the lower distal end of the top.
An improved pull-string attachment system is disclosed by Hedeen in U.S. Pat. No. 6,146,233 wherein the pull string has a toothed catch at one end which engages with a cylindrical hub of the top. This arrangement results in the string being wound within a deep radial groove transverse to the spin axis rather than the string being wound on the exterior lower surface of the top.
In U.S. Pat. No. 4,960,401, Ross teaches a spinning top having a minimal size and weight which, when used in combination with a coin, exhibits significantly improved spinning and balance properties. Parodi has also invented a spinning top in U.S. Pat. No. 4,129,961 which includes a flexible belt or strap to impart spinning rotation replacing the conventional string or cord.
The present invention enhances the spinning capability of a spinning top by the addition of a precision bearing positioned between a pointed replaceable lower tip of the spinning top and the lower body portion of the hollow body of the top. This bearing arrangement significantly increases the time for free spinning of the top while also facilitating the easy replacement of worn lower pointed tips. Additionally an annular ring is also provided formed of a substantially higher density material such as brass which greatly enhances the rotational inertia of the spinning top without a proportionate increase in overall weight, the hollow body being molded of plastic material to mob achieve a more optimal inertia/weight relation.
This invention is directed to a spinning top including a balanced hollow body having a vertical spin axis and including an upper and a lower body portion rigidly connected together directly or preferably interconnected by a weighted annular ring for increased rotational inertia. A replaceable pointed tip is connected to the lower end of the lower body portion for free rotation with respect to the body, the pointed tip engaging against a support surface when the body is placed into a spinning motion. A second bearing-mounted upper pointed tip may be releasably connected concentric with the spin axis and upwardly extending from an upper end of the upper body portion whereby the spinning top may be lifted from one support surface and placed onto another support surface without interrupting spinning motion of the top.
It is therefore an object of this invention to provide a spinning top with extended rotational time after being spun and released.
It is yet another object of this invention to provide a replaceable lower pointed tip of a spinning top which is also bearing-mounted for free rotation with respect to the body of the spinning top for enhanced rotational characteristics by the reduction of friction both at the pointed tip on a support surface and between the pointed tip and the body of the spinning top.
It is still another object of this invention to provide a spinning top with a disproportionately high ratio of rotational inertia to weight as facilitated by the addition of an annular ring or band of substantially higher density material than that utilized in mold-forming plastic body of the spinning top.
Yet another object of this invention is to provide a pointed tip attached to both upper and lower ends of a spinning top, each pointed tip being held for free relative rotation with respect to the body of the spinning top for enhanced usage opportunities.
In accordance with these and other objects which will become apparent hereinafter, the instant invention will now be described with reference to the accompanying drawings.